text: /*
   * Copyright (c) 2013, 2014 Nicira, Inc.
   *
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at:
   *
   *     http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  
  /* This header implements atomic operation primitives on Clang. */
  #ifndef IN_OVS_ATOMIC_H
  #error "This header should only be included indirectly via ovs-atomic.h."
  #endif
  
  #define OVS_ATOMIC_CLANG_IMPL 1
  
  #define ATOMIC(TYPE) _Atomic(TYPE)
  
  #define ATOMIC_VAR_INIT(VALUE) (VALUE)
  
  #define atomic_init(OBJECT, VALUE) __c11_atomic_init(OBJECT, VALUE)
  
  /* Clang hard-codes these exact values internally but does not appear to
   * export any names for them. */
  typedef enum {
      memory_order_relaxed = 0,
      memory_order_consume = 1,
      memory_order_acquire = 2,
      memory_order_release = 3,
      memory_order_acq_rel = 4,
      memory_order_seq_cst = 5
  } memory_order;
  
  #define atomic_thread_fence(ORDER) __c11_atomic_thread_fence(ORDER)
  #define atomic_signal_fence(ORDER) __c11_atomic_signal_fence(ORDER)
  
  #define atomic_store(DST, SRC) \
      atomic_store_explicit(DST, SRC, memory_order_seq_cst)
  #define atomic_store_explicit(DST, SRC, ORDER) \
      __c11_atomic_store(DST, SRC, ORDER)
  
  
  #define atomic_read(SRC, DST) \
      atomic_read_explicit(SRC, DST, memory_order_seq_cst)
  #define atomic_read_explicit(SRC, DST, ORDER)   \
      (*(DST) = __c11_atomic_load(SRC, ORDER), \
       (void) 0)
  
  #define atomic_compare_exchange_strong(DST, EXP, SRC)                   \
      atomic_compare_exchange_strong_explicit(DST, EXP, SRC,              \
                                              memory_order_seq_cst,       \
                                              memory_order_seq_cst)
  #define atomic_compare_exchange_strong_explicit(DST, EXP, SRC, ORD1, ORD2) \
      __c11_atomic_compare_exchange_strong(DST, EXP, SRC, ORD1, ORD2)
  
  #define atomic_compare_exchange_weak(DST, EXP, SRC)              \
      atomic_compare_exchange_weak_explicit(DST, EXP, SRC,         \
                                            memory_order_seq_cst,  \
                                            memory_order_seq_cst)
  #define atomic_compare_exchange_weak_explicit(DST, EXP, SRC, ORD1, ORD2) \
      __c11_atomic_compare_exchange_weak(DST, EXP, SRC, ORD1, ORD2)
  
  #define atomic_exchange(RMW, ARG) \
      atomic_exchange_explicit(RMW, ARG, memory_order_seq_cst)
  #define atomic_exchange_explicit(RMW, ARG, ORDER) \
      __c11_atomic_exchange(RMW, ARG, ORDER)
  
  #define atomic_add(RMW, ARG, ORIG) \
      atomic_add_explicit(RMW, ARG, ORIG, memory_order_seq_cst)
  #define atomic_sub(RMW, ARG, ORIG) \
      atomic_sub_explicit(RMW, ARG, ORIG, memory_order_seq_cst)
  #define atomic_or(RMW, ARG, ORIG) \
      atomic_or_explicit(RMW, ARG, ORIG, memory_order_seq_cst)
  #define atomic_xor(RMW, ARG, ORIG) \
      atomic_xor_explicit(RMW, ARG, ORIG, memory_order_seq_cst)
  #define atomic_and(RMW, ARG, ORIG) \
      atomic_and_explicit(RMW, ARG, ORIG, memory_order_seq_cst)
  
  #define atomic_add_explicit(RMW, ARG, ORIG, ORDER) \
      (*(ORIG) = __c11_atomic_fetch_add(RMW, ARG, ORDER), (void) 0)
  #define atomic_sub_explicit(RMW, ARG, ORIG, ORDER) \
      (*(ORIG) = __c11_atomic_fetch_sub(RMW, ARG, ORDER), (void) 0)
  #define atomic_or_explicit(RMW, ARG, ORIG, ORDER) \
      (*(ORIG) = __c11_atomic_fetch_or(RMW, ARG, ORDER), (void) 0)
  #define atomic_xor_explicit(RMW, ARG, ORIG, ORDER) \
      (*(ORIG) = __c11_atomic_fetch_xor(RMW, ARG, ORDER), (void) 0)
  #define atomic_and_explicit(RMW, ARG, ORIG, ORDER) \
      (*(ORIG) = __c11_atomic_fetch_and(RMW, ARG, ORDER), (void) 0)
  
  #include "ovs-atomic-flag-gcc4.7+.h"
  